Hydrocarbon contamination and oil spills cause significant economic and environmental damage. Crude oil and refined fuel spills have damaged an array of ecosystems ranging from arctic and tundra in Alaska and Russia, to tropical and subtropical regions (e.g., the Gulf of Mexico). While the amount of oil released in an accident is a major factor in estimating the severity of the contamination (e.g., from a few hundred tons to several hundred thousand tons (e.g., Deepwater Horizon Oil Spill, Atlantic Empress, Amoco Cadiz)) it is a combination of the amount of the material and the location of the spill that provides a gauge of the cost of resources and impact on the environment. Smaller spills, such as the Exxon Valdez for example, can have a large impact on an ecosystem because of the remoteness of the site or the difficulty is launching and maintaining an emergency environmental response.
In light of the continuing increase in the demand for energy, oil spills are a persistent risk and consequence of fossil fuel-based energy production. In order to meet the increasing global demand for oil, activities surrounding oil exploration, production, and processing are also likely to increase. This, in turn, increases the opportunities for environmental contamination arising from oil production. Oil spills may result from the release of crude oil (or refined petroleum products (such as gasoline, diesel fuel, kerosene) and their by-product wastes) from tankers, offshore platforms, drilling rigs wells, pipelines, and storage containers or containment vessels. Oil spills are notoriously difficult to contain and clean up in marine areas (e.g., oceans and coastal waters) as well as freshwater rivers and lakes, but spills that occur on land may also be difficult to clean up, and may also pose immediate safety concerns (e.g., due to breakages or spillages associated with storage/containment vessels or transport pipelines, and exposure near population centers). Typically, however, oil spills on land are more readily containable by using techniques such as building makeshift earth dams around the spill site, and land animals can avoid the oil more easily relative to aquatic life. Marine spills are particularly challenging to contain and clean up since they can spread for hundreds of nautical miles in a thin oil slick which can eventually spread to and contaminate beaches with a thin coating of oil, or as agglomerates (e.g., “tar balls”). Oil slicks can kill all varieties of sea life, including sea birds, sea mammals, fish, shellfish and other organisms that it comes in contact with and/or coats.
Cleanup and recovery from an oil spill is difficult and depends upon many factors, including the type of oil spilled, the temperature of the water (affecting evaporation and biodegradation), and the types of shorelines and beaches involved. Spills may take weeks, months or even years to clean up. As such, the existing methods that are used to remove oil contaminants from an ecosystem and for cleaning and restoring the environment are not adequate. For example, there is a huge economic cost for clean-up strategies that strategies that use oil dispersant technology, such as used in the Deep Water Horizon accident. Furthermore using dispersants may dissipate the observable oil slicks, oil agglomerate “chocolate mousse,” and tarballs, but they do not remove the oil or contaminating hydrocarbons from the environment. Current research coming from the Gulf waters that were exposed to the Deep Water Horizon accident is showing that chemical dispersants such as Corexit (e.g., Corexit 9527A and 9500A), may combine with crude oil to make it more bioavailable and significantly more toxic to marine organisms, particularly smaller and/or microscopic organisms such as Rotifera. (See, Rico-Martinez, R., et al., Environmental Pollution (February 2013) 173:5-10; epub November 2012). Therefore, not only are the current strategies for containment and clean-up of hydrocarbon contamination extremely expensive, the techniques and reagents used in the existing strategies may be causing more environmental damage and causing more toxicity to native flora and fauna than would the oil on its own.
Accordingly, there is a continuing need for new strategies for lessening or eliminating the prolonged impact of hydrocarbon pollutants, such as those associated with oil production and processing, and that help to restore the exposed environment and contaminated flora and fauna to its natural state.